My 42 DCM service grade with 43 barrel is still a tack driver. Most can be brought to acceptable utility with proper servicing and good parts. The net it full of dealers with nos parts. Orion 7, Fulton, etc., are great sources to make your m1 a great rifle.
My brother in law bought 2 on line from the CMP 1 the Service the other a collector grade. He really lucked out on the service grade. It's an H&R with all H&R parts except for the op rod. The stock is excellent and has not been sanded or reworked in any way and has all the proper cartouches and still had 95% of the original parkerizing. The muzzle read a 1 the chamber a 2. I wasn't impressed by the collector grade as it had all commercial would and was repacked SA. He got the 2 about 4 months ago.